Epidemiology and general guidelines of the management of acquired haemophilia and von Willebrand syndrome

Atypical acquired hemophilia linked with primary biliary cholangitis: a unique case presentation

Acquired hemophilia A is an uncommon disease often presented with bleeding episodes causing a significant mortality risk. The main responsible for the threatening hemorrhagic disorder is the Factor VIII autoantibody's development. Acquired inhibitors' presence is frequently idiopathic, but it can be associated with malignancy, pregnancy, drugs and autoimmune diseases. In this report, we present the first case of acquired hemophilia A associated with primary biliary cholangitis. A 48-year-old man, presented with diffuse oral bleeding after a tooth extraction. Hemostasis testing revealed a markedly prolonged activated partial thromboplastin time. The search for an anti-factor VIII inhibitor returned positive. The etiological investigation concluded primary biliary cholangitis, and the patient was treated with bypassing agent, immunosuppressive therapy, and ursodeoxycholic acid.

Integrated Approach to Highlighting the Molecular Bases of a Deep Vein Thrombosis Event in an Elite Basketball Athlete

Acute or intense exercise can result in metabolic imbalances, muscle injuries, or reveal hidden disorders. Laboratory medicine in sports is playing an increasingly crucial role in monitoring athletes' health conditions. In this study, we designed an integrated approach to explore the causes of a deep venous thrombosis event in an elite basketball player. Since the complete blood count revealed a marked platelet count (838 × 103 µL), and thrombophilia screening tests did not reveal any significant alteration, we evaluated the thrombin generation, which highlights a state of hypercoagulability. First-level haemostasis exams showed only a slight prolongation of the activated Partial Thromboplastin Time (aPTT). Thus, screening tests for von Willebrand Disease showed a reduction in vWF parameters. Therefore, we directed our hypothesis towards a diagnosis of acquired von Willebrand disease secondary to Essential Thrombocythemia (ET). To confirm this hypothesis and highlight the molecular mechanism underlying the observed phenotype, molecular tests were performed to evaluate the presence of the most common mutations associated with ET, revealing a 52-bp deletion in the coding region of CALR exon 9. This case report highlights the importance of an integrated approach to monitoring the athletes' health status to personalise training and treatments, thus avoiding the appearance of diseases and injuries that, if underestimated, can undermine the athlete's life.

Acquired von Willebrand syndrome: Five cases report and literature review

Acquired von Willebrand syndrome is a rare bleeding disorder with laboratory findings similar to those of inherited von Willebrand disease. Principal factors distinguishing acquired von Willebrand syndrome from the latter condition include lack of prior bleeding disorders, diagnosis at older age, negative family history and association with underlying conditions.

METHODS

Retrospective, monocentric descriptive case series of acquired von Willebrand syndrome diagnosed between 2010 and 2020. Diagnostic criteria included a recent history of bleeding, a negative family history and a presence of underlying disorders.

RESULTS

Five men were diagnosed with acquired von Willebrand syndrome. All of them presented with recent mucocutaneous bleeding. The biological phenotype was a type 2 von Willebrand disease in all cases, with decreased VWF:RCo/VWF:Ag and VWF:CB/VWF:Ag ratios (<0.7). Lymphoproliferative, autoimmune and cardiovascular diseases were the main underlying conditions identified. Screening for an anti-von Willebrand factor inhibitor was positive in two patients. Four patients received treatment for the underlying disorder. High-dose intravenous immunoglobulins were the most frequent treatment administrated. Improvement of plasma von Willebrand factor levels was observed in four cases.

CONCLUSION

Acquired von Willebrand syndrome is a rare but potentially serious disease. The diagnostic should be suspected in adults with unusual mucocutaneous bleeding associated with lymphoproliferative, myeloproliferative, autoimmune and cardiovascular disorders.

The Intriguing Connections between von Willebrand Factor, ADAMTS13 and Cancer

von Willebrand factor (VWF) is a complex and large protein that is cleaved by ADAMTS13 (a disintegrin and metalloproteinase with thrombospondin type 1 motif, member 13), and together they serve important roles in normal hemostasis. Malignancy can result in both a deficiency or excess of VWF, leading to aberrant hemostasis with either increased bleeding or thrombotic complications, as respectively seen with acquired von Willebrand syndrome and cancer-associated venous thromboembolism. There is emerging evidence to suggest VWF also plays a role in inflammation, angiogenesis and tumor biology, and it is likely that VWF promotes tumor metastasis. High VWF levels have been documented in a number of malignancies and in some cases correlate with more advanced disease and poor prognosis. Tumor cells can induce endothelial cells to release VWF and certain tumor cells have the capacity for de novo expression of VWF, leading to a proinflammatory microenvironment that is likely conducive to tumor progression, metastasis and micro-thrombosis. VWF can facilitate tumor cell adhesion to endothelial cells and aids with the recruitment of platelets into the tumor microenvironment, where tumor/platelet aggregates are able to form and facilitate hematogenous spread of cancer. As ADAMTS13 moderates VWF level and activity, it too is potentially involved in the pathophysiology of these events. VWF and ADAMTS13 have been explored as tumor biomarkers for the detection and prognostication of certain malignancies; however, the results are underdeveloped and so currently not utilized for clinical use. Further studies addressing the basic science mechanisms and real word epidemiology are required to better appreciate the intriguing connections between VWF, ADAMTS13 and malignancy. A better understanding of the role VWF and ADAMTS13 play in the promotion and inhibition of cancer and its metastasis will help direct further translational studies to aid with the development of novel cancer prognostic tools and treatment modalities.

Von Willebrand Factor Multimeric Assay in Acquired von Willebrand Disease Diagnosis: A Report of Experience from North Estonia Medical Centre

Objectives Acquired von Willebrand syndrome (AVWS) is a rare and frequently underdiagnosed bleeding disorder with an unknown prevalence. The diagnosis of AVWS is made based on laboratory investigations and the presence of clinical symptoms. Evaluation and management of affected patients are complex due to the need for multiple laboratory assays.

Materials and Methods Here, we describe the clinical and laboratory data of seven patients with a diagnosis of AVWS. All patients met the criteria for AVWS based on laboratory findings, bleeding symptoms, and the absence of any previous history of a bleeding disorder.

Results In all cases, the laboratory findings, lack of bleeding anamnesis, and family history suggested the presence of AVWS. Von Willebrand factor multimeric analysis showed decreased high-molecular weight (HMW) multimers in six cases. Patients with lower HMW multimers experienced more severe bleeding complications.

Conclusions The diagnosis of AVWS is complex and requires extensive laboratory evaluation. Interdisciplinary collaboration and complex laboratory evaluations are of paramount importance for the early recognition of AVWS and optimal AVWS diagnosis as well as successful clinical management.

Management of rare acquired bleeding disorders

Autoantibodies toward clotting factors may develop in people suffering from autoimmune or neoplastic diseases, after drug intake or even in subjects without apparent conditions. They are more commonly directed against factor VIII (FVIII) or von Willebrand factor leading to acquired hemophilia A or acquired von Willebrand syndrome, respectively. Rarely, autoantibodies develop against other clotting factors, such as fibrinogen, FII, FV, FVII, FX, FXI, and FXIII. The clinical picture of an acquired bleeding disorder includes a wide spectrum of clinical manifestations ranging from minimal or no bleeding to life-threatening events. Patients with no previous personal or family history of bleeding may have sudden-onset hemorrhagic manifestations, sometimes fatal, especially if an early diagnosis is not made. On the other hand, some patients may not have hemorrhagic symptoms at onset, and their diagnosis can therefore be delayed. The laboratory diagnostic assessment is performed by screening coagulation tests followed by specific factor-level measurement and inhibitor-titrating assays. An early diagnosis of acquired coagulopathies is mandatory for starting the appropriate treatment aimed at both controlling the acute bleeding episode mainly using the bypassing agents, and eradicating the anticlotting factor autoantibody, using immunosuppressive treatment. Therefore, prompt intervention by an expert and a specialized center is needed for immediate recognition and treatment of the disease.

Clinical evaluation of bleeds and response to haemostatic treatment in patients with acquired haemophilia: A global expert consensus statement

BACKGROUND

Acquired haemophilia (AH) is a rare bleeding disorder with significant morbidity and mortality. Most patients initially present to physicians without experience of the disease, delaying diagnosis and potentially worsening outcomes. Existing guidance in AH is limited to clinical opinion of few experts and does not address monitoring bleeds in specific anatomical locations.

AIM

Derive consensus from a large sample of experts around the world in monitoring bleeding patients with AH.

METHODS

Using the Delphi methodology, a structured survey, designed to derive consensus on how to monitor bleeding patients with AH, was developed by a steering committee for completion by a group of haematologists with an interest in AH. Consensus was defined as ≥75% agreement with a given survey statement. After three rounds of survey refinement, a final list of consensus statements was compiled.

RESULTS

Thirty-six global specialists in AH participated. The participants spanned 20 countries and had treated a median of 12.0 (range, 1-50) patients with AH within the preceding 5 years. Consensus was achieved in all items after three survey rounds. In addition to statements on general management of bleeding patients, consensus statements in the following areas were presented: urinary tract, gastrointestinal tract, muscles, skin, joints, nose, pharynx, mouth, intracranial and postpartum.

CONCLUSIONS

Here, we present consensus statements derived from a broad sample of global specialists to address monitoring of location-specific bleeds and evaluating efficacy of bleeding treatment in patients with AH. These statements could be applied in practice by treating physicians and validated by individual population surveys.

Acquired Hemophilia A Presenting as Intramuscular Hematoma

Acquired hemophilia A poses a clinical and diagnostic challenge. Although rare, it is still the most common acquired factor deficiency. We present a case of acquired hemophilia A diagnosed in a 71-year-old female who presented with a right thigh hematoma of acute onset. The diagnosis was established based on the coagulation profile along with factor VIII levels, mixing studies, and inhibitor levels. The patient received multiple lines of therapy including steroids, factor VIIa, Obizur (porcine-derived recombinant factor VIII), followed by multiple cycles of chemotherapy including cyclophosphamide and rituximab.

Prevention and Management of Bleeding Episodes in Patients with Acquired Hemophilia A

Acquired hemophilia A (AHA) is a rare autoimmune disease caused by autoantibodies inhibiting the function of coagulation factor VIII. It is characterized by spontaneous bleeding in patients with no previous family or personal history of bleeding. Although several large registries have collected clinical data on AHA, limited information is available on the optimal management of AHA because controlled clinical trials are lacking. AHA can easily be diagnosed if the problem (prolonged activated partial thromboplastin time in a bleeding patient) is recognized. After the effects of anticoagulants are excluded, low factor VIII activity and the detection of circulating inhibitors confirms the diagnosis. However, lack of familiarity with this rare condition may delay diagnosis and adequate therapy. Treatment of AHA is based on measures for prompt hemostatic control to stop (and prevent) bleeding, immunosuppression to eradicate the autoantibodies, and supportive care for the adverse effects of that treatment and patients' often complex comorbidities. This article gives a comprehensive overview of the current knowledge about the pathophysiology, diagnosis, and treatment of AHA.

A Case Report of Anticoagulation Management in Acquired Hemophilia Associated With Levofloxacin

PURPOSE

To report a case of acquired hemophilia secondary to levofloxacin and provide a guide for the use of anticoagulation in acute coronary syndrome.

CASE SUMMARY

A 75-year-old female treated with levofloxacin presented with spontaneous bruising of the upper extremities. Levofloxacin was discontinued and the symptoms resolved. Thereafter, the spontaneous bruising recurred and progressed over a few weeks. The patient was treated with recombinant factor VIIA with a time to recuperation of 3 months. The patient was subsequently found to have ST-segment elevation for which they received unfractionated heparin, ticagrelor, and aspirin prior to bare metal stent placement.

CONCLUSION

Hemophilia A is a rare disease associated with high morbidity and mortality. Case studies previously evaluating the association of levofloxacin with acquired hemophilia have shown causality. Initiating anticoagulation in patients with acquired hemophilia has long been a challenge to clinicians as evidence-based guidelines are lacking and bleeding risk may outweigh the benefit of anticoagulation. Furthermore, factor VIII deficiency does not provide additive protection against atherosclerotic plaque formation. This case report supports existing literature associating levofloxacin with acquired hemophilia. Due to the complication of life-threatening bleeds, familiarity with the treatment course following coronary events will allow patients with acquired hemophilia to be adequately and safely anticoagulated.

Acquired Hemophilia A: Experience of a Tertiary Care Institute from North India

Acquired hemophilia A (AHA) is an uncommon bleeding disorder infrequently reported among Indians. The present retrospective data comprises eight cases of AHA over a period of 15 years. The mean age of patients was 59.7 years. The activated partial thromboplastin time was prolonged in all cases and the inhibitor screen showed the presence of inhibitors. Factor VIII: C assay was performed in 7 cases and all cases demonstrated low levels. Lupus anticoagulant was negative. Six patients were managed with steroids and symptomatic supportive care. These patients were followed up for a mean period of 3.5 years (range 1-5 years). Of these, there was one fatality prior to initiation of therapy and one patient continues to have inhibitors.

Acquired von Willebrand Syndrome Complicating Nephrotic Syndrome: A Case of a Patient With Membranous Nephropathy

Acquired von Willebrand syndrome (AVWS) is a rare clinical entity presenting with heterogeneous hemorrhagic manifestations, although some subsets of patients with AVWS may be asymptomatic until they are exposed to major trauma, an invasive procedure, or surgery. We herein report one such case in a 73-year-old male patient with nephrotic syndrome with a prolonged active partial thromboplastin time. We initially did not deal with this distinct abnormal clotting profile seriously, but persistent bleeding after a retroperitoneoscopic-assisted renal biopsy that allowed us to ascribe his nephrotic syndrome to membranous nephropathy fortuitously led to the discovery of concurrent AVWS. We feel that an accurate and prompt diagnosis as well as awareness of the disease remain a challenge for physicians and therefore strongly recommend the further accumulation of experiences similar to our own in a prospective manner. This report underscores the pitfalls associated with determining the bleeding risk, including an insufficient assessment and improper weighting of an abnormal clotting profile prior to the invasive procedure. Several management concerns that emerged in the current case are also discussed.

A global quantitative survey of hemostatic assessment in postpartum hemorrhage and experience with associated bleeding disorders

Purpose

Coagulopathy may be a serious complicating or contributing factor to postpartum hemorrhage (PPH), and should be promptly recognized to ensure proper bleeding management. This study aims to evaluate the approaches of obstetrician-gynecologists worldwide towards assessing massive PPH caused by underlying bleeding disorders.

Methods

A quantitative survey was completed by 302 obstetrician-gynecologists from 6 countries (the UK, France, Germany, Italy, Spain, and Japan). The survey included questions on the use of hematologic laboratory studies, interpretation of results, laboratory’s role in coagulation assessments, and experience with bleeding disorders.

Results

Overall, the most common definitions of “massive” PPH were >2,000 mL (39%) and >1,500 mL (34%) blood loss. The most common criteria for rechecking a “stat” complete blood count and for performing coagulation studies were a drop in blood pressure (73%) and ongoing visible bleeding (78%), respectively. Laboratory coagulation (prothrombin time/activated partial thromboplastin time [PT/aPTT]) and factor VIII/IX assays were performed on-site more often than were mixing studies (laboratory coagulation studies, 93%; factor VIII/IX assays, 63%; mixing studies, 22%). Most commonly consulted sources of additional information were colleagues within one’s own specialty (68%) and other specialists (67%). Most respondents had consulted with a hematologist (78%; least, Germany [56%]; greatest, UK [98%]). The most common reason for not consulting was hematologist unavailability (44%). The most commonly reported thresholds for concern with PT and aPTT were 13 to 20 seconds (36%) and 30 to 45 seconds (50%), respectively. Most respondents reported having discovered an underlying bleeding disorder (58%; least, Japan [35%]; greatest, Spain [74%]).

Conclusion

Global survey results highlight similarities and differences between countries in how PPH is assessed and varying levels of obstetrician-gynecologist experience with identification of underlying bleeding disorders and engagement of hematology consultants. Opportunities to improve patient management of PPH associated with bleeding disorders include greater familiarity with interpreting PT/aPTT test results and identification of and consistent consultation with hematologists with relevant expertise.

Assessment of acquired hemophilia patient demographics in the United States: the Hemostasis and Thrombosis Research Society Registry

The Hemostasis and Thrombosis Research Society (HTRS) Registry was used to monitor the postapproval use of recombinant factor VIIa. The objective of this manuscript is to provide key insights on the demographics of patients with acquired hemophilia in the HTRS Registry. Acquired hemophilia patient registration in HTRS captured age; sex; comorbidities and predisposing conditions; first bleeding location; laboratory parameters; exposure to blood products, factor, and bypassing agents; and initiation of immune suppression/tolerance therapy. Overall, 166 patients with acquired hemophilia were registered in HTRS (83 women, 73 men, median age 70 years); the majority were non-Hispanic whites (61.4%). The most common comorbidities were autoimmune disease (28.4%) and malignancy (14.5%). The most common first site of bleeding was subcutaneous (27.1%); this was more common in whites (29.1%) than blacks (12.5%) and in non-Hispanics (26.4%) than Hispanics (11.8%). Blood product exposure was reported for 33.1% of patients; the most commonly reported product was packed red blood cells (28%). Of the 57 patients with outcome data available for immune tolerance therapy, 26 patients (46%) reported successful treatment, 13 reported unsuccessful treatment (23%), and 18 (32%) were receiving active treatment at the time of registration. The HTRS Registry final analysis provides the only current comprehensive look at acquired hemophilia in the US population, including details on underlying autoimmune diseases and malignancies. Pertinent to recognition and diagnosis of the disease, subcutaneous bleeding as a presenting bleeding symptom was more common in white and non-Hispanic individuals.

Factors predisposing to acquired von Willebrand syndrome during the course of polycythemia vera - retrospective analysis of 142 consecutive cases

INTRODUCTION

The aim of this study was to verify if PV patients with and without avWS differ in terms of their baseline clinical parameters.

MATERIAL AND METHODS

The study included 142 consecutive patients with PV. avWS was diagnosed on the basis of abnormally low levels of von Willebrand factor and other routine tests. Patients with and without concomitant avWS were compared in terms of their demographic characteristics, present and past medical histories and laboratory parameters.

RESULTS

Concomitant avWS was found in 17 PV patients (12.0%). Individuals with avWS have been diagnosed with PV at significantly younger age than those without, and significantly less often were in remission at the time of testing for bleeding disorders. Most of them (58.8%) presented with typical signs of bleeding disorder. Moreover, they showed significantly higher erythrocyte, leukocyte and platelet counts, abnormalities of coagulation profile corresponding to defects of primary hemostasis and abnormal values of all parameters used in the routine diagnosis of avWS.

CONCLUSIONS

Even every tenth patient with PV may develop avWS. Young age at diagnosis of PV and poor response to previous treatment of this condition are potential risk factors of avWS that should be considered during history taking. Sings of bleeding disorder observed in a person with PV necessitate evaluation for avWS.

Combination of FVIII and low-dose rFVIIa improves haemostasis in acquired haemophilia A patients: a collaborative controlled study

INTRODUCTION

Acquired haemophilia A (AHA) is an autoimmune disease that potentially leads to severe bleeding and has a high rate of mortality. This collaborative study aimed to assess the efficacy of the co-administration of FVIII and low-dose rFVIIa in patients with AHA.

MATERIALS AND METHODS

This study retrospectively compared the combined FVIII/low-dose rFVIIa therapy (initial dose range of 25-55μg/Kg) with the combined FVIII/PCC therapy and low-dose rFVIIa monotherapy. Adverse drug reactions and recurrent bleeding episodes were also monitored. Crude comparisons and the exact conditional logistic regression were performed to compare the outcomes between three treatment groups.

RESULTS

First bleeding episodes of 56 consecutive patients from 5 centres were analyzed, and 37 bleeding episodes (66.1%) were determined to be severe. Specifically, the rate of bleeding control was significantly higher with the FVIII/low-dose rFVIIa therapy compared to that of the low-dose rFVIIa alone therapy or the FVIII/PCC therapy (58.3% vs. 41.7% vs. 95.0%, respectively). Analyzing of total 236 bleeding episodes showed a clear positive association between the early initiation of haemostatic treatment and efficacy. No therapy-related adverse events in which thrombosis predominated were reported.

CONCLUSIONS

The combination of FVIII and low-dose rFVIIa offers an ideal haemostatic cover and may be promoted as a feasible and safe therapy protocol for patients with AHA.

Thalidomide for treatment of gastrointestinal bleedings due to angiodysplasia: a case report in acquired von Willebrand syndrome and review of the literature

INTRODUCTION

Acquired von Willebrand syndrome is a rare bleeding disorder and treatment of the associated gastrointestinal (GI) bleeding due to angiodysplasia is challenging.

AIM

The aim of this study was to present a new case on the successful use of thalidomide in a patient with acquired von Willebrand syndrome and recurrent angiodysplasia-related GI bleedings, and to conduct a literature review on the use of thalidomide in patients with GI angiodysplasia.

METHODS

A literature review was conducted, searching the electronic databases PubMed, Embase and Cochrane.

RESULTS

We present a 75-year-old woman with IgG MGUS-associated acquired von Willebrand syndrome (AVWS) who suffered from recurrent gastrointestinal (GI) bleedings and epistaxis. Treatment with immunoglobulins, desmopressin, Haemate-P and blood transfusions failed to achieve long-term haemostasis. Eventually, after these bleedings relapsed for almost a decade at 1- to 3-month intervals, thalidomide was prescribed. Since then, only one single nose bleed and one single melaena episode had occurred. She currently remains in remission of GI bleeds after 3 years and 3 months follow-up. The literature review revealed a beneficial effect of thalidomide in reducing GI bleeding due to angiodysplasia, including four case reports on inherited von Willebrand disease.

CONCLUSION

In conclusion, thalidomide can be a reasonable option for the treatment of recurrent GI bleeding due to angiodysplasia in AVWS and we report for the first time that refractory or relapsing GI bleeding in patients with AVWS can successfully be controlled with thalidomide.

Supportive transfusion therapy in cancer patients with acquired defects of hemostasis

Bleeding occurs in approximately 10% of patients with cancer: supportive transfusion therapy with Platelets Concentrates (PC), Fresh Frozen Plasma (FFP) and plasma-derived or recombinant concentrates is often required for the cessation and prevention of the bleeding episodes. The most frequent causes of bleeding in cancer is thrombocytopenia followed by liver insufficiency with or without vitamin K deficiency, disseminated intravascular coagulation (DIC) and the inappropriate or excessive use of anticoagulants. Other acquired hemostatic defects such as acquired hemophilia (AHA) and acquired von Willebrand syndrome (AVWS) are rare but they can be life-threatening. Thrombocytopenia in cancer patients may be the consequence of marrow invasion, chemotherapy or platelet auto-antibodies; patients with severe hypoproliferative thrombocytopenia, must be treated with PC and carefully followed to assess refractoriness to PC. The management of the other acquired defects of hemostasis usually requires the use of FFP and specific plasma-derived or recombinant concentrates. PC, FFP and plasma-derived concentrates can induce complications and/or adverse events in cancer patients: these include mainly allergic (ALR) or anaphylactic reactions (ANR), Transfusion-Associated Graft-Versus-Host Disease (TA-GVHD), Trasfusion-transmitted bacteriemia (TTB), Transfusion-Related Acute Lung Injury (TRALI), Acute Hemolytic Transfusion Reactions (AHTR), Febrile Non Hemolytic Transfusion Reactions (FNHTR). Therefore, modifications such as leukocyte-reduction and irradiation of the blood components to be transfused in cancer patients are recommended to reduce the risk of these complications.

Dos and don'ts in diagnosing antiphospholipid syndrome

Antiphospholipid syndrome (APS) is an acquired autoimmune thrombotic tendency that is identified by the presence of abnormal antiphospholipid laboratory tests in patients who have a history of vascular thrombosis and/or pregnancy complications including recurrent spontaneous miscarriages and a group of other complications due to placental insufficiency. Diagnostic testing for APS is often problematic because of many misconceptions regarding these empirically derived assays. This chapter is intended to provide hematology-oncology consultants with practical information about the uses and limitations of assays used to diagnose APS.

Acquired von Willebrand syndrome associated with monoclonal gammopathy: a single-center study of 36 patients

In this single-center retrospective study, we evaluated the accuracy of laboratory tests in diagnosing acquired von Willebrand syndrome associated with lymphoproliferative disorders in 36 consecutive patients diagnosed at the University Hospital of Nantes, France. We also compared hemostatic treatments in the following groups: 21 patients with Waldenström macroglobulinemia (WM), 14 with monoclonal gammopathy of undetermined significance (MGUS) (10 with IgG-MGUS and 4 with IgM-MGUS), and 1 with IgA multiple myeloma (IgA-MM). The diagnosis was made in 18 (50%) patients during systematic screening, in 6 (17%) during active mild hemorrhage, and in 12 (33%) during an active, severe bleed. Of the laboratory tests studied, only closure times measured on the Platelet Function Analyzer (PFA)-100 device reliably diagnosed the hemostatic problem. There was no relationship between the factor VIII activity (FVIII:C) or von Willebrand factor activity (VWF:RCo) levels and the previous history of hemorrhage described by patients.We studied hemostatic treatment in most patients: IgG-MGUS patients responded well to high-dose intravenous immunoglobulin (IVIg) infusions (1 g/kg per d), although patients with IgM-MGUS did not. Desmopressin infusions were effective in 3 patients with IgG-MGUS and 2 patients with IgM-MGUS when the baseline values were above 10 IU/dL, but levels soon returned to the baseline. The 7 WM patients had a good response to desmopressin. These results confirm the efficacy of IVIg in IgG-MGUS patients and the prominent role of closure time in the diagnosis of acquired von Willebrand syndrome.

How I treat the acquired von Willebrand syndrome

The acquired von Willebrand syndrome (AVWS) is a bleeding disorder that is frequently unrecognized or is misdiagnosed as von Willebrand disease. AVWS is characterized by structural or functional defects of von Willebrand factor (VWF) that are secondary to autoimmune, lymphoproliferative or myeloproliferative, malignant, cardiovascular, or other disorders. VWF abnormalities in these disorders can result from (1) antibody-mediated clearance or functional interference, (2) adsorption to surfaces of transformed cells or platelets, or (3) increased shear stress and subsequent proteolysis. Diagnosis can be challenging as no single test is usually sufficient to prove or exclude AVWS. Furthermore, there are no evidence-based guidelines for management. Treatments of the underlying medical condition, including chemo/radiotherapy, surgery, or immunosuppressants can result in remission of AVWS, but is not always feasible and successful. Because of the heterogeneous mechanisms of AVWS, more than one therapeutic approach is often required to treat acute bleeds and for prophylaxis during invasive procedures; the treatment options include, but are not limited to, desmopressin, VWF-containing concentrates, intravenous immunoglobulin, plasmapheresis or recombinant factor VIIa. Here, we review the management of AVWS with an overview on the currently available evidence and additional considerations for typical treatment situations.

Acquired hemophilia: a rare but life-threatening potential cause of bleeding in the intensive care unit

OBJECTIVE

There are a number of potential etiologies of severe bleeding encountered in the intensive care unit. Although rare, acquired hemophilia is one such etiology that often presents with major bleeding requiring intensive care. Despite the introduction of effective treatments, the reported mortality rate of patients with acquired hemophilia ranges from 6 to 8% and is in part attributable to sequential delays in diagnosis and appropriate treatment. The purpose of this review is to familiarize the intensive care specialist with this underrecognized cause of bleeding, with an emphasis on diagnosis and treatment.

METHODS

As the objective of this article was to provide a concise overview of the diagnosis and management of acquired hemophilia, a directed search of English-language literature was undertaken using the PubMed database, targeting such topics as the differential diagnosis of bleeding in the intensive care unit and the epidemiology, diagnosis, and treatment of acquired hemophilia. Clinical study findings pertaining to the efficacy of specific treatments for acquired hemophilia were summarized.

RESULTS AND CONCLUSION

Recognition of acquired hemophilia presents a clinical challenge, given the rarity of this condition, a general lack of familiarity with acquired hemophilia, and the potential for confusion with other more common causes of bleeding in the intensive care unit. Nevertheless, there are sentinel clinical and laboratory findings that should raise suspicion of this diagnosis. The treatment of acquired hemophilia is a multi-step, physiologically focused process aimed at controlling both active and recurrent bleeding. Therefore, prompt diagnosis is central to prognosis. Consultation with a hematologist may facilitate efficient diagnosis and management.

Acquired haemophilia a in the elderly: case reports

Acquired hemophilia A (AHA) is a very rare disease, caused by the development of autoantibodies, directed against circulating factor VIII of coagulation. Age distribution is bimodal, with a first peak occurring among young women in the postpartum period, and a second major peak of incidence among elderly patients in whom it is frequently associated with malignancy and drugs. This disease often represents a life-threatening bleeding condition, especially in the elderly, thus requiring a prompt therapeutic intervention, including control of acute bleeding and eradication of the inhibitor by immunosuppressive therapy. The diagnosis of AHA should be considered in any elderly patient who presents with bleeding and prolonged activated Partial Thromboplastin Time. Moreover, the coexistence of a series of underlying diseases associated with AHA should be always searched for. An early recognition and an adequate treatment of this coagulation disorder and of the possible associated diseases play a significant role for a favourable outcome, but concomitant morbidities in the elderly may limit aggressive therapy and may complicate the clinical scenario. We report 3 consecutive elderly patients successfully treated with recombinant activated factor VII and standard immunosuppressive regimens, with remission of the disease.

The laboratory approach to inherited and acquired coagulation factor deficiencies

Besides the long-recognized hemophilias, there are many other factor deficiencies. Some also are inherited, but others are acquired because of both immune and nonimmune etiologies. Understanding the optimal laboratory approach to evaluating factor deficiency will aid physicians and laboratory scientists in obtaining a prompt diagnosis and in avoiding pitfalls in coagulation testing.

Mechanisms underlying acquired von Willebrand syndrome associated with an IgM paraprotein

Acquired von Willebrand (vW) syndrome is a rare bleeding disorder which is frequently associated with immunological, malignant or cardiovascular disorders. The underlying pathomechanisms, particularly in patients with IgM monoclonal gammopathies, often remain unknown. We report a patient with indolent small B-cell lymphoma (immunocytoma) and plasmacytic differentiation with an IgM kappa paraprotein who was admitted with retroperitoneal haematoma. Medical history and coagulation testing were consistent with acquired vW syndrome. vW immunohistochemistry showed normal cytoplasmic labelling of endothelial cells and megakaryocytes, whereas the lymphomatous infiltrate was negative. Acquired vW syndrome due to adsorption of vW factor on malignant cells was thus excluded. In the multimeric analysis, all multimers were present similar to that in type 1 vW syndrome, but the triplet structures were blurred. The bands on serum immunofixation electrophoresis were also atypically broadened, which suggested complex formation between the IgM and vW factor. Immunoprecipitation studies showed that the 176-kDa proteolytic fragment of vW factor co-precipitated with the IgM paraprotein in the patient but not in the controls, suggesting a specific interaction between vW factor and the paraprotein in the patient. The patient required surgery and was successfully managed by chemotherapy consisting of rituximab and fludarabin as well as plasma exchange.

The treatment of hemophilia A: from protein replacement to AAV-mediated gene therapy

Factor VIII (FVIII) is an essential component in blood coagulation, a deficiency of which causes the serious bleeding disorder hemophilia A. Recently, with the development of purification level and recombinant techniques, protein replacement treatment to hemophiliacs is relatively safe and can prolong their life expectancy. However, because of the possibility of unknown contaminants in plasma-derived FVIII and recombinant FVIII, and high cost for hemophiliacs to use these products, gene therapy for hemophilia A is an attractive alternative to protein replacement therapy. Thus far, the adeno-associated virus (AAV) is a promising vector for gene therapy. Further improvement of the virus for clinical application depends on better understanding of the molecular structure and fate of the vector genome. It is likely that hemophilia will be the first genetic disease to be cured by somatic cell gene therapy.